It is a moral challenge riding herd on all the apostates on this comments section! I being one of those ‘undesirables’ . Your polemic is impressive, in its way, yet your faith in the morally upright Mr. Mueller reminds me of David Bromwich’ s essay at The London Review of Books:

Comey’s memoir has now surpassed the combined sales of Michael Wolff’s portrait of the Trump White House, Fire and Fury, and Hillary Clintons’s election elegy What Happened. The book, written in an idiom identical to the one he uses in interviews and press briefings, is clearly the work of an un-ghosted author, and it contains passages most unusual for an official memoir:

There is a place I have visited on the coast of North Carolina where two barrier islands come close together. In the narrow passageway between them, the waters of the Atlantic Ocean meet the waters of the huge and shallow sound that lies behind the islands. There is turbulence in that place and waves appear to break even though no land is visible. I imagine that the leaders of the Department of Justice stand at that spot, between the turbulent waters of the political world and the placid waters of the apolitical sound. Their job is to respond to the political imperatives of the president and the voters who elected him, while also protecting the apolitical work of the thousands of agents, prosecutors, and staff who make up the bulk of the institution. So long as the leaders understand the turbulence, they can find their footing. If they stumble, the ocean water overruns the sound and the department has become just another political organ. Its independent role in American life has been lost and the guardians of justice have drowned.

This depth of formal piety cannot be faked; the passage shows the burden (as Comey sees it) of maintaining constitutional and legal restraints on Donald Trump.

I’ve placed in bold what I think is relevant to your faith in Mueller, as mirrored in Bromwich’s faith in Comey. The mendacity of the FBI, and its record of political nihilism is exemplified by J.Edgar Hoover and his exercise of unchecked power over generations. Consider the latest cover up of the 20 year record of its ‘Crime Lab’ incompetence to be just the recent of its self-servingly mendacious incompetence!